Tuesday, Jan 8, 2013 - 2:00 AM
"Alien Invasion"
This program explores the impact that invasive species and viruses have on environmental and human health around the world. Increasingly, foreign animal and plant species jump national and international boundaries and wreak havoc on ecosystems that offer no natural resistance or predators to the unwelcome guests. Alda looks at some of the most egregious aliens and what's being done to control them. D